If you want to assemble a well finished zipper you should use these stops., Sold as a set of 3 pieces, one in the shape of an X for the lower part
Universal YKK top stop (stopper): an essential part of every zipper. The top stop closes the zipper and prevents the slider from coming out. The
YKK Zipper Top Stop - Nickel Free
YKK Zipper Repair Kit Solution 8 Sets Assorted 4 of #5, 2 of #7 and 2 of #10 Included Top & Bottom Stops Made in USA Antique Auto Lock Sliders, Black
Zipper Stops
Zipper Stops Top & Bottom Stop - Weaver Leather Supply
YKK Zipper stops - Leather Artisan Lab
VISLON® with Revived Top Stop
Zipperstop Wholesale - Zipper Repair Kit Solution 9 Sets YKK Auto Lock Sliders Assorted 3 of #3, 2 of #5, 2 of #7 and 2 of #10 Included Top & Bottom
Zip Sliders, Zip Top & Bottom Stops Australia
YKK Zipper stops - Leather Artisan Lab
Tandy Leather #5 Zipper Top Stop Brass 10/Pk 58052-030
Zip Sliders, Zip Top & Bottom Stops Australia
Tandy Leather #10 Zipper Top Stop Brass 10 Pack 58102-030